"Tania, Gemma, Netty, Paula, Anni," reads the note attached to a bunch of fading pink roses left in tribute to the five murdered Ipswich sex workers. "I knew some of you better than others. But I miss you all. X Tom."

The flowers have been tied to a lamp-post next to a police cabin, erected last week at the junction of London Road and Handford Road on the corner of Ipswich's red light district. This is the very spot, a former sex worker told the Guardian yesterday, at which Tom Stephens would park his car most evenings and wait for the women working in the area to walk past, or to call him.

Yesterday Mr Stephens was being interviewed by police at an undisclosed location, after being arrested on suspicion of the five murders, which he denies. In an interview with a Sunday paper the day before his arrest, he admitted having paid for sex in the past with at least some of the women who were killed, but described himself as "a friend to all the girls" and their "protector". "If I was out there tonight, if there was a girl working, I would try to watch over her," he told the Sunday Mirror. "But I'd tell her, 'I can't keep you safe.' I'd try to give her some sort of support. Some of them have nobody else at all."

Most of the women who worked in Ipswich knew Mr Stephens well, said Jackie Goldsmith, the former sex worker, and would call him frequently to ask him to drive them to their dealers to buy drugs, or just let them sit in his car to warm up. Some women would have sex with him in return, others would not. On other occasions he would pay for sex. She was shocked at the news of the arrest. "It's not him. No way. He's just Tom. He would rather help them than kill him."

The women who Tom Stephens met in Ipswich's red light area, a place he began to frequent 18 months ago, knew little of his respectable middle-class background. It was only a few days before she died that Annette Nicholls, one of the dead women, told her friend Ms Goldsmith: "Did you know Tom was a copper?"

Tom Stephens was born in Ipswich on May 27 1969. As a young boy his mother, Ellen, and father, Douglas, divorced, and he moved with his mother and brother, Jack, a year his junior, to Blowfield, near Norwich, where Mrs Stephens took up a job as a teacher at Hemblington primary school. He was known as a quiet boy by his schoolfriends at Thorpe St Andrews school in Norwich, a specialist sports college. "He used to wear really tight trousers, he was very uncool," one said yesterday. "He would hang around on the outside of groups, a bit of a nerd." As a young boy he loved sport, particularly football.

By the age of 23 he was living in Norwich and working as a special constable with Norfolk police. He would patrol central Norwich, which includes the red light district, and was said by a friend to love the job. In 1997 he left the force and the area, moving to Ipswich where in February 1998 he married Judith Kirk, a nurse.

A fitness fanatic who said on his MySpace website that he loved sport, Mr Stephens had an idiosyncratic hero: Hong Kong Phooey, the children's cartoon character. He also gave himself a nickname, The Bishop.

During his marriage he lived with his wife in a semi-detached Victorian house in Cavendish Street, on the eastern outskirts of Ipswich.

Around 2003 they separated, and Mr Stephens moved to a flat in Pearson Road, sharing with three others and paying £280 a month for a single room. "He was an ordinary tenant," said Stuart Kantor, the estate manager. "He never held parties, he was never noisy. We are all amazed that anyone like that could be arrested."

Mr Stephens had no car at the time, and would cycle the five miles to his job at the 24-hour Tesco in the village of Martlesham, east of Ipswich, where he worked shifts.

In September of this year, he moved to a 1960s semi-detached home in Jubilee Close, Trimley St Martin, close to Felixstowe. He would drive his purple two-door Renault Clio up the A14 to the supermarket, a few hundred yards from the Suffolk police headquarters. Early yesterday morning his car had been taken away on a flatbed lorry.

Neighbours in Trimley said they did not know Mr Stephens well. His ex-wife, a nurse in Ipswich, stayed away from her home yesterday. Samantha Gray, a close friend, said: "I spoke to her at the weekend and she said she was very upset about something. She asked me not to say anything if anyone came round here."

Mr Stephens' mother, who is remarried and lives in Eye, Suffolk, is also unwell, her husband Richard Kite said yesterday, declining to comment further. Mr Stephens regularly visited his mother, helping to look after her during her illness. He said in his interview with the Sunday Mirror that he had disclosed to his mother very recently that he had turned to prostitutes and had known all of the dead women well. The news, he said, had hit his mother like "a bolt from the blue".

Mr Stephens' father, Douglas Stephens, who lives in the Northamptonshire village of Isham in a £360,000 stone cottage, told the Guardian: "There is nothing I can say. I am his father yes, but I don't want to say anything further."

The arrested man's brother, Jack Stephens, who lives with his partner in Sprowston, Norwich, was not at home yesterday. His partner, Dawn Royal, refused to comment.

Mr Stephens' family had not seen him recently; he appeared to be spending increasing amounts of time with the prostitutes in Ipswich.

Ms Goldsmith told the Guardian that she last saw Mr Stephens on Friday night, when he came round to her flat close to the red light district to talk about the murders. "He just wanted to chat because he was upset and pretty down," she said. Since the first women disappeared he had been calling her every night to check she was all right and to discuss the news. "He had all of their numbers. Most of the girls who were working would have known Tom. The girls trusted him."

Mr Stephens grew very attached to two of the women, Tania Nicol and Gemma Adams. He bought Ms Nicol the glittery stiletto shoes she was wearing on the night she died, and which police are still looking for.

Some of the women had become used to his attentions, the former sex worker said. For the girls he was just another punter. He was a bit persistent. He would hang about ... outside their houses."

At the same time as calling on the women who worked the streets, it appears Mr Stephens was also contacting tabloid journalists offering to speak about the dead women, and the fact that he had been interviewed by police, for a fee. He also talked to the BBC, telling them: "I wanted sex and I paid for it but I befriended the girls."

Ms Goldsmith was particularly surprised at Mr Stephens' arrest because none of the women appear to have been sexually assaulted, whereas, she said: "He's after sex. He's all for sex."

Mr Stephens' message on MySpace states: "Well here I am trying to make my laptop work and I've ended up here." Under "Who'd I'd like to meet", his reply is: "Goddoh" [Godot]. Under the heading "children" he says: "Love kids but not for me." He states his occupation as team leader in Tesco "from 1997 until they sack me".

He last visited the site on October 27. He has posted several pictures, including one of him wearing a union flag tie and another in what appears to be fancy dress, with his eyes rimmed with black kohl. He says he is single and is looking for a serious relationship and friends.

Detectives will be questioning Mr Stephens about his relationship with the women, while examining his home and his car for any forensic evidence. He acknowledged to the Sunday Mirror that he could be a suspect, but insisted he had nothing to do with the murders.

At her home at Eye, Suffolk, Mr Stephens' elderly mother was also visited by detectives last night. For the answer to why her son decided to pay women for sex, she has what he said in his own words.

"I am sad and lonely," he told the Sunday Mirror. "I made compromises on my morals to go down [to the red light area] the first time, so I suppose getting involved with them isn't a huge leap. They would quite often want a lift to get their drugs and I would give them a lift. It was better for me like that. That is how it developed into a friendship."